Numerical and Experimental Validation of Three-Dimensional Shock Control Bumps

Abstract

Numerical and experimental studies have been performed to show the potential for drag reductions of an array of discrete three-dimensional shock control bumps. The bump contour investigated was specifically designed by means of computational-fluid-dynamics-based numerical optimization for wind-tunnel testing on a modern transonic airfoil. The experimental investigations focused on turbulent flow at a Reynolds number of 5 million and were carried out at the Transonic Wind Tunnel Gottingen. Drag reductions of around 10% in the drag-rise region were found in the experiment even though the results were influenced by wind-tunnel interference effects. A detailed numerical study of the wind-tunnel environment reproduced the influence of the wind-tunnel walls on the bump performance and gave good agreement to the experimental results.